I use Color Flashlight HD. It gives you a choice of using the screen or LED. The LED mode is kind of nice, showing a switch on the screen to toggle the LED on and off so that the phone resembles a square flashlight.

Moto Torch did not work at all.

Will look into Droid Light.... only because I would like one that lets me put a toggle widget on the home screen for quicker access.

Edit: Droid Light works, but no widget. Frankly, you may as well use Color Flashlight HD. It just looks cooler than having a Light Bulb on the screen.